The rules are the only language dependent thing in this game.
Your son might like it. I think it is a bit too fiddly. If he likes "cool" components, he might also enjoy the features in this game.
/Strömer, from Sweden
"Fiddly" is one of those keywords on BGG that doesn't really mean much. People seem to use it whenever they don't enjoy a game, but just because a game isn't your thing, that doesn't mean there's anything necessarily "fiddly" about it.
I think any kid could understand Technowitches really easily. Especially since the game teaches everyone how to play it in four increasingly complex game variants. I've played it with very young children and they picked it up easily. It's one of my favorite truly All Ages games and the rules do a terrific job of simulating a racing dynamic.
Anyone can learn this game and be playing it in minutes, including kids (and even thick-headed non-gamers).